When life boats are launched it is required that the releasing devices located at the fore and aft of the boat be manually swung to their opening position when the boat has reached the water surface and the load on the lowering tackles has substantially ceased, so that the boat is released. The releasing device comprises a hook and a supporting lifting member, which is fixed to the keel of the boat and which is so designed that the release mechanism cannot be actuated when the boat is hanging in the tackles, i.e. when the hooks are loaded. It has occurred that even after launching the pull in the hoisting cable is so great that the hooks are not manually swingable and a release is not possible. Such a great pull can e.g. exist if the ship still has a speed despite the life boats being launched or if the ship is in strongly streaming water, but also if the ship is sinking fast this situation can occur. Since the hoisting cables usually consists of steel wires and heavy blocks it is not possible to cut oneself loose from the ship by means of an axe or the like.